// Copyright 2016 The Draco Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef DRACO_COMPRESSION_MESH_MESH_ENCODER_H_
#define DRACO_COMPRESSION_MESH_MESH_ENCODER_H_

#include "draco/compression/attributes/mesh_attribute_indices_encoding_data.h"
#include "draco/compression/point_cloud/point_cloud_encoder.h"
#include "draco/mesh/mesh.h"
#include "draco/mesh/mesh_attribute_corner_table.h"

namespace draco {

    // Abstract base class for all mesh encoders. It provides some basic
    // functionality that's shared between different encoders.
    class MeshEncoder : public PointCloudEncoder {

        public:

            MeshEncoder();

            // Sets the mesh that is going be encoded. Must be called before the Encode()
            // method.
            void SetMesh( const Mesh &m );

            EncodedGeometryType GetGeometryType () const override {

                return TRIANGULAR_MESH;
            }

            // Returns the number of faces that were encoded during the last Encode().
            // function call. Valid only if "store_number_of_encoded_faces" flag was set
            // in the provided EncoderOptions.
            size_t num_encoded_faces () const {

                return num_encoded_faces_;
            }

            // Returns the base connectivity of the encoded mesh (or nullptr if it is not
            // initialized).
            virtual const CornerTable *GetCornerTable() const {

                return nullptr;
            }

            // Returns the attribute connectivity data or nullptr if it does not exist.
            virtual const MeshAttributeCornerTable *GetAttributeCornerTable (
                    int /* att_id */ ) const {

                return nullptr;
            }

            // Returns the encoding data for a given attribute or nullptr when the data
            // does not exist.
            virtual const MeshAttributeIndicesEncodingData *GetAttributeEncodingData (
                    int /* att_id */ ) const {

                return nullptr;
            }

            const Mesh *mesh() const {

                return mesh_;
            }

        protected:

            Status EncodeGeometryData () override;

            // Needs to be implemented by the derived classes.
            virtual Status EncodeConnectivity () = 0;

            // Computes and sets the num_encoded_faces_ for the encoder.
            virtual void ComputeNumberOfEncodedFaces () = 0;

            void set_mesh ( const Mesh *mesh ) {

                mesh_ = mesh;
            }

            void set_num_encoded_faces ( size_t num_faces ) {

                num_encoded_faces_ = num_faces;
            }

        private:

            const Mesh *mesh_;
            size_t num_encoded_faces_;
    };

}  // namespace draco

#endif  // DRACO_COMPRESSION_MESH_MESH_ENCODER_H_
